Make the embedder responsible for creating the WebFrame

Source/web/WebHelperPluginImpl.cpp

Index: Source/web/WebHelperPluginImpl.cpp
diff --git a/Source/web/WebHelperPluginImpl.cpp b/Source/web/WebHelperPluginImpl.cpp
index 8c8197482ffa061298f97bfc5122111cfde9dcba..50c147ff889d0ebcc73d67ef3e51182a417cdd0f 100644
--- a/Source/web/WebHelperPluginImpl.cpp
+++ b/Source/web/WebHelperPluginImpl.cpp
@@ -109,6 +109,7 @@ private:
 WebHelperPluginImpl::WebHelperPluginImpl(WebWidgetClient* client)
     : m_widgetClient(client)
     , m_webView(0)
+    , m_mainFrame(0)
 {
     ASSERT(client);
 }
@@ -143,13 +144,14 @@ void WebHelperPluginImpl::closeHelperPlugin()
         // closeWidgetSoon() will call this->close() later.
         m_widgetClient->closeWidgetSoon();
     }
+    m_mainFrame->close();
 }
 
 void WebHelperPluginImpl::initializeFrame(WebFrameClient* client)
 {
     ASSERT(m_page);
-    RefPtr<WebFrameImpl> frame = WebFrameImpl::create(client);
-    frame->initializeAsMainFrame(m_page.get());
+    m_mainFrame = WebFrameImpl::create(client);
+    m_mainFrame->initializeAsMainFrame(m_page.get());
 }
 
 // Returns a pointer to the WebPlugin by finding the single <object> tag in the page.